Number of binary codes (not necessarily linear) of length n with 5 words.

Terms

a(0) =0a(1) =0a(2) =3a(3) =27a(4) =131a(5) =497a(6) =1606a(7) =4647a(8) =12320a(9) =30493a(10) =71218a(11) =158374a(12) =337375a(13) =691981a(14) =1371917a(15) =2637956a(16) =4932911a(17) =8992413a(18) =16013007a(19) =27904818a(20) =47663115a(21) =79909497a(22) =131666339